This 10-foot-long Crocodile Is an Entirely New Species to Science

Scientists have identified a new species of crocodile in New Guinea—the world's second-largest island—that measures up to ten feet in length, according to a study.

Researchers already knew about one crocodile that is unique to the tropical island—the New Guinea Crocodile (Crocodylus novaeguineae) first described in 1928.

But now Chris Murray from Southeastern Louisiana University and Caleb McMahan from the Field Museum of Natural History in Chicago have found sufficient differences between two groups of Crocodylus novaeguineae living in the north and south of the island, respectively, to identify one as a new species.

Murray and McMahan decided to investigate the issue after hearing about research carried out by the late scientist Philip Hall from the University of Florida, who had documented important differences in the nesting and mating behavior of the New Guinea crocodiles living in the north and south of the island.

For a study published in the journal Copeia, the researchers examined 51 skulls from animals previously thought to represent the species Crocodylus novaeguineae that were being kept at several museums across the U.S.

They then inspected live New Guinea crocodiles housed at the St. Augustine Alligator Farm Zoological Park in Florida to see if the variations they had identified in the skulls could be seen in real life. Eventually, they were able to discern noticeable differences between crocodiles from the north and south of the island.

"We could even look at a skull that they had there and tell what river it came from. So our analyses really did a good job at teasing apart where these things are from," Murray said.

The differences between the northern and southern crocodiles were sufficient for the pair to describe those from the south as a separate species.

"The nice thing is that here we've got differences in the morphology, we've got ecological differences, they're separated by a mountain range, I think the synthesis of all of that is what really builds the case that these two crocodile entities are very different from each other," McMahan said.

The team decided to name the new species Crocodylus halli in honor of Hall, who had begun investigating the differences between the northern and southern crocodiles but passed away before his work came to fruition.

"Those early discussions we had were based on the fascinating ecological work of Philip Hall," McMahan told Newsweek. "It was an easy decision to name this new species after him in recognition of his work."

The researchers say that the latest findings could have significant implications for conservation efforts.

"Nearly all crocodilians have protective measures or recommendations in place. We are now working with two, instead of one, species of crocodile in the region. If habitats are far worse overall in one area over another, this means something for the now endemic species occurring on each side of the mountain range," McMahan said.

There are only 13 known species of crocodile living in tropical habitats around the world, making Crocodylus halli the 14th. While new species are discovered all the time, the identification of new large animals, such as crocodiles, is rare.

"There are new species out there but a lot of them are sitting in drawers and cabinets in museums, and it just takes time to look at them and figure that out," McMahan said.

new crocodile species, Crocodylus halli
A member of the newly-described species of crocodile, living at a zoological park in Florida. American Society of Ichthyologists and Herpetologists